1. The Field of the Invention
This invention concerns improvements in and relating to processing of materials, particularly, but not exclusively to the processing of nuclear fuel materials, materials involved in the nuclear fuel cycle and materials involved i the nuclear fuel industry.
2. The Relevant Technology
The production of fuel grade nuclear fuel is a long and complicated process. For instance, starting from mined uranium ore, in general terms the process involves taking the ex-mine grade material and gradually converting and enriching it until it is in a form and of a grade suitable for the production of fuel pellets.
Prior art systems for converting the ore into material suitable for enrichment, by physical or chemical means, have almost invariably involved a series of wet chemical techniques. For instance, the initial uranium oxide is concentrated in a uranyl nitrate hexahydrate based state; with a de-nitration stage to convert the material into UO3; this is then reduced to convert the UO3 to UO2; with a hydro-fluorination stage to form UF4 and further fluorination subsequently UF6, which is fed to the enrichment procedures used.
Similar complex chemical and physical steps, generally involving wet chemistry, are used in the recycling of spent fuel and other uranium containing feeds.